The cleaning and disinfecting of hard surfaces is important in both residential and commercial settings. The increasing importance of hygiene combined with the fast moving pace of the modern world has created a need for products with fast cleaning and disinfecting action. The main concerns are to effectively reduce bacteria and maintain a consumer acceptable aesthetics profile while producing an acceptable human and environmentally safe composition. As will be appreciated, this implicitly puts constraints on the amount and type of chemicals that can be used to formulate a commercially acceptable composition.
Within the European Union disinfecting products are regulated through the Biocidal Product Directive/Regulation, aiming at restricting the use of hazardous disinfecting agents while otherwise setting minimum efficacy requirements for disinfecting product compositions behind the European Union standard suspension test, European Norm 1276 (EN1276). This EN1276 test is a standard test for the evaluation of the effectiveness of biocidal compositions in the European Union. The test was designed to simulate dirty conditions and allows for evaluating a product simultaneously exposed to cleaning and disinfecting. Organic soils and hard water are known to interfere with the activity of biocides, so the use of interfering substances, namely bovine albumin (0.3%) and hard water), represent the soil likely to be found when cleaning. The use of these interfering substances in the presence of quantitatively and qualitatively known bacteria (Pseudomonas aeruginosa, Escherichia coli, Staphylococcus aureus, Enterococcus hirae) ensures a rigorous test standard under dirty conditions. To pass EN1276 and, as such, to claim to be a disinfectant product, a log 5 reduction (99.999% kill) of the bacteria must be attained within 5 minutes at an 80% product concentration at 20 degrees Celsius.
Very few formulations are described in the literature passing this challenging testing protocol. For example, one formulation, for skin and hospital disinfection purposes, passes the EN1276 success criteria using very high solvent levels, especially alcohols. However, a formulation high in solvents would not be satisfactory as a household detergent composition, including hand dishwashing detergents, due to viscosity, product odor, product labeling and formulation cost constraints.
Yet another example in the literature describes a formulation that passes the EN1276 protocol using a mixture of two antibacterial agents combined with a sequesterant, solvent and/or surfactant. However, such a formulation is also unsatisfactory in a household detergent composition because of increased costs, supply chain concerns and increased overall formula incompatibility risk when formulating multiple different raw materials.
As such, there remains a need for a cleaning and disinfecting product that provides a log 5 bacterial kill under the EN1276 European Union standard suspension test and maintains a consumer acceptable aesthetics profile while producing an acceptable human and environmentally safe composition.